By ARNOLD LETSHOLO

Residents of the Okavango region have been commended for their role in preserving the exceptional water quality of the Okavango Delta, with experts attributing this achievement largely to traditional cultural practices and indigenous knowledge systems.

Speaking in an interview, geoscientist and National Geographic Explorer Dr. Goabaone Jaqueline Ramatlapeng highlighted the vital role that local communities continue to play in protecting one of the world’s most pristine freshwater ecosystems.

“Their indigenous knowledge systems and cultural values have long contributed to the Delta’s exceptional ecological health,” said Dr. Ramatlapeng, whose research in hydrogeochemistry and water resources spans across Southern Africa.

“Local communities use natural resources in sustainable, low-impact ways, including traditional fishing, reed harvesting, and mokoro transport. These practices do not introduce oil, fuel, or industrial waste into the water.”

Many water bodies in the Delta are regarded as spiritually significant, which has cultivated a culture of respect and conservation among residents. These beliefs discourage pollution and encourage seasonal use and rotational access to water sources, helping to ease pressure on specific areas.

“This ethical relationship with nature acts as an informal conservation code that helps protect water quality,” she explained. “Waste management practices in remote areas, including composting, use of pit latrines, and minimal chemical usage, further reduce the risk of water contamination.”

She also praised residents for participating in conservation programs, including Community-Based Natural Resource Management (CBNRM) initiatives and eco-tourism partnerships.

These efforts include environmental education, citizen science programs such as water monitoring, tree planting, and reporting of illegal dumping.

Despite limited infrastructure, she said, the people of the Okavango Delta have embraced conservation and sustainability in ways that ensure the Delta remains viable for future generations.

“These efforts reflect an inherent understanding of the Delta as a living system that must be respected and carefully managed,” she said.

According to Dr. Ramatlapeng, the overall quality of water in the Okavango Basin remains high due to factors such as low industrial activity, sparse populations, and the natural filtration capabilities of the floodplains and wetlands. However, emerging threats are beginning to affect various parts of the basin.

In Angola, the expansion of agriculture and artisanal mining is leading to concerns about heavy metal contamination. In Namibia, agricultural activities and poor waste disposal practices are impacting water quality.

In Botswana, while the Delta acts as a natural biogeochemical filter, growing urban runoff from Maun, livestock grazing, and climate-related changes pose new challenges.

One of the pressing threats is the spread of the invasive aquatic plant Salvinia molesta, which affects water quality by forming dense mats that block light and oxygen.

Dr. Ramatlapeng noted that the spread of this plant is being effectively managed through biological control using the Salvinia Weevil, a host-specific beetle that feeds exclusively on the plant.

“This method is safe, effective, and aligns with our goal to preserve the Delta’s biodiversity,” she said. “Other methods such as chemical control or mechanical removal carry risks that could further degrade water quality or spread the infestation.”

She emphasized the importance of a coordinated transboundary response to manage the basin’s water resources, citing the role of the Okavango River Basin Water Commission (OKACOM) and other regional partnerships.

Dr. Ramatlapeng called for integration of scientific monitoring, hydrogeochemical research, and indigenous knowledge systems in managing the basin.

Dr. Ramatlapeng, who holds a Ph.D. in Earth and Planetary Sciences from the University of California, Davis, continues to conduct research on the spatial and temporal changes in water chemistry in arid environments.

Her message was clear: while scientific innovations and international frameworks are important, the local knowledge and cultural values of Okavango communities remain central to preserving one of the last remaining unspoiled freshwater ecosystems on the planet.

(C) TPA2025